Transcript International Atomic Energy Agency PROTECTIVE EQUIPMENT L6 Answer True or False • Technologists need not bother with gloves • or lab coats when injecting a.

International Atomic Energy Agency
PROTECTIVE EQUIPMENT
L6
Answer True or False
• Technologists need not bother with gloves
•
or lab coats when injecting a patient with
18F-FDG, as it is not absorbed by the skin
and washes off quite easily
The positrons emitted by 18F travel only a
few mm in water, so no special radiation
protection precautions are needed, and
syringes containing 18F-FDG can be
handled just like any other syringe filled
with saline
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Objective
To consider protective equipment for
reduction of staff doses in cyclotron and
PET/CT facilities, including shielding,
handling devices and personal protective
equipment (PPE)
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Content
• Shielding
• Handling radionuclides
• PPE
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International Atomic Energy Agency
6.1 Shielding
Shielding
• For 511 keV typically 30-50 mm lead
• For 99mTc (140 keV) usually 3 or 6 mm
• Biggest problem with 511 keV shielding
is the weight (density of lead 11 kg/litre)
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Transport Case
Liner
Lead container
(47-57 mm )
Container
Weight 15-25 kg
Source
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Syringe Shields
99mTc-
18F-FDG
(2 mm
tungsten)
(8 mm
tungsten)
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Dose rate from FDG using Various Syringe Shields
Syringe shield
uSv/hr/MBq
200
150
100
50
0
Unshielded
8mm tungsten
2 mm tungsten
2 cm perspex
4cm perspex
Type of syringe shield
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Storage of Radionuclides
Storage safe (sources and
waste)
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50 mm lead
Various sizes
Weight 500-1500 kg
Reduces dose rate by 10-3
Security for removal
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Storage of Solid Waste
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Shielded bins for papers,
gloves, empty vials and
syringes.
Separate bins for active and
non-active waste
Contaminated linen must be
stored for 24 hours in
protected cupboard before
removal to laundry
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Dispensing
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Dispensing unit
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Additional lead L block
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50 mm lead thickness
Weight 25 kg
Reduces dose rate by 10-3
30 mm lead thickness
Weight 250 - 500 kg
Need to consider loading
on work surface due to
weight of lead
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Calibrators
• Calibrators may need extra
shielding
• Work surfaces may need
strengthening to take the weight
of extra lead
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International Atomic Energy Agency
6.2 Handling
PET Radiopharmacy Lab
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Drawing Up
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Calculate volume
required
Gloves
Long handle forceps or
tongs
Only fill syringe to 50%
capacity
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Long Forceps - 30 cm
• Reduce dose by 60%
compared with 18 cm
tools
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Calibrator
Calibrator ‘sunk’ into
worktop helps to reduce
exposure time of operator
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Worktop Surfaces
• Cover the surface with absorbing paper
•
or disposable tray
Change daily or when spill is suspected
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Administration of Radiopharmaceuticals
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Butterfly or cannula for venous access
Syringe shield
Carry shielded syringe to patient in
additional shielding
Gloves
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Remote Injection System (Lemer Pax)
• Connect to patient
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by catheter
Manually activated
remote system
Operator behind
protective screen
30 mm lead shielding
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International Atomic Energy Agency
6.3 Personal Protective Equipment
Personal Protective Equipment (BSS)
“I.28.
Employers, registrants and licensees shall ensure that:
(a)
workers be provided with suitable and adequate personal
protective equipment which meets any relevant standards or
specifications, including as appropriate:
(i)
protective clothing;
………..
(iii)
protective aprons and gloves and organ shields;
………..
(b)
all personal protective equipment be maintained in proper
condition and if appropriate be tested at regular intervals;
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Personal Protective Equipment (BSS)
cont.
(c)
appropriate personal protective equipment be maintained
for use in the event of intervention; and
(d)
the use of personal protective equipment is considered for
any given task, account be taken of any additional exposure that
could result owing to the additional time or inconvenience, and of
any additional non-radiological risks that might be associated with
performing the task while using protective equipment. ”
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Personal Protective Equipment
Unsealed Radioactive Material
• Gloves
• White coat
• Aprons, etc.
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Personal Protective Equipment
CT
• Lead apron 0.35 mm
• Thyroid shield
• Only required for those
who must remain in
room during scanning,
e.g. contrast injection
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SUMMARY OF PROTECTIVE EQUIPMENT
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The 511 keV gamma rays emitted by 18F are more
penetrating than the 140 keV gamma rays emitted by
99mTc, so special precautions are needed when
handling syringes containing 18F-FDG, including the
use of long forceps in handling vials and syringe
shields and L blocks specifically intended to shield
positron emitters
It is important for technologists to use gloves and lab
coats whenever handling positron emitters, so as to
be able to easily decontaminate themselves
It is important for personnel involved in PET/CT
scanning to protect themselves from the CT exposure,
especially if their presence is ever required in the
room while the CT scan is in progress
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